Despite having no real plot or structure, Yume Nikki does in fact have an ending scene.
The mere existence of the ending is only alluded to in-game, with the cryptic Instructions saying to "drop effects in the door room", although there is no indication of what the purpose of this is.
At first, the simple act of dropping all the effects in the Nexus appears to have no result, and there is no indication that anything has changed. Only when the player ventures out onto the balcony in the real world does the nature of the ending become apparent.
The Ending SequenceEdit
After collecting all 24 effects (25 including the Instructions) in the game, Madotsuki must return to the Nexus. She then drops every last one of her effects (by equipping them and pressing the '5' key).
Madotsuki then leaves the dream world by pinching herself awake. She explores her room, and finds that a set of stairs have appeared on the balcony, leading over the railing.
Madotsuki climbs the stairs, jumps off the side of the balcony and plummets downward, then everything becomes dark.
A heavy, echoing thud breaks the silence, and a pool of blood fades into view. Two Jellyfish from her dream world approach from different directions and surround the red smear as the credits appear, and the mournful ending theme begins to play.
Some fans have theorized that the real world is actually another layer of the many dream worlds in the game. This could explain how Madotsuki's eyes are always closed, how the set of stairs suddenly appeared on the balcony, and why the Jellyfish appear. The manga supports this by having Masada tell her that the only way to wake up for real is to kill herself (see below), although this was not made by KIKIYAMA themself.
The Jellyfish could be seen as a sign that even in death, Madotsuki won't escape her nightmares, or they could also be interpreted as humans in the real world spectating what happened to her, appearing as monsters.
- The Jellyfish can be interacted with on the ending screen, pressing the number keys causes them to chime. The lower Jellyfish reacts to the (1) key and makes a higher-pitched sound, and the upper Jellyfish reacts to the (3) key and makes a lower sound.
- It is speculated that the Falling Men could, in fact, be foreshadowing the ending.
- Interestingly, the same pool of blood can be found in various worlds in the game, such as Mural World, Eyeball World, and Underground World.